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Researchers To Build Underwater Airplane
Posted by
ScuttleMonkey
on Mon Oct 06, 2008 01:51 PM
from the journey-to-the-bottom-of-the-sea dept.
from the journey-to-the-bottom-of-the-sea dept.
coondoggie writes to tell us that DARPA seems to still be having fun with their funding and continues to aim for the "far out." The latest program, a submersible airplane, seems to have been pulled directly from science fiction. Hopefully this voyage to the bottom of the sea is of the non-permanent variety. "According to DARPA: 'The difficulty with developing such a craft come from the diametrically opposed requirements that exist for an airplane and a submarine. While the primary goal for airplane designers is to try and minimize weight, a submarine must be extremely heavy in order to submerge underwater. In addition, the flow conditions and the systems designed to control a submarine and an airplane are radically different, due to the order of magnitude difference in the densities of air and water.'"
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Steve Fossett (Score:2)
Re:Steve Fossett (Score:5, Informative)
Linky [slashdot.org]
Steve Fossett's Unfinished Project
Posted by kdawson on Sunday October 05, @02:36AM
from the ocean-flying dept.
Transportation Science Technology
MazzThePianoman writes "Steve Fossett left behind a secret vessel project called the Deep Flight Challenger. Fossett was funding the development of a winged submersible being designed by Hawkes Ocean Technologies in California. The intent was for the vehicle to be capable of travel to the very bottom of the ocean -- the Mariana Trench, more than 11,000 meters beneath the surface. 'It would have dramatically, dramatically opened the oceans for exploration. It would have been a game changer,' said Graham Hawkes, the designer. Testing had been completed at Department of Defense facilities. Field testing was only four weeks away when Fossett's untimely death, a year ago, put the project on hold." Hawkes Ocean Technologies owns the design but the vehicle itself is owned by Fossett's estate.
Parent
Re:Steve Fossett (Score:4, Informative)
No, this is an airplane that can also be a submarine (and surface vessel). Fossett was financing a sub that "flew" underwater.
Parent
What is a flight? (Score:3, Interesting)
Airplanes fly through the air
Zeppelins and balloons fly through the air
Submarines fly through the water
Space-ships fly out of atmosphere
Ships do not fly because their motion is in between two media
Cars do not fly (except for some instants, as it is the case of Rally cars jumping
From an engineering point of view, submarines use buoyancy force
Utterly Wrong (Score:5, Informative)
I work with ex-submariners. One of the reasons that they hated and feared a real reactor SCRAM was that the sub was essentially relying on its forward motion to maintain it's depth.
Yes, it was negatively buoyant, but the slight upward pitch of its planes enabled it to "fly" through the water. Supposedly, you get much more responsive control that way, rather than wallowing in the water while you wait for tanks to fill or empty. Very important, when you're trailing an aggressive Russian sub...
When the reactor shuts down and the screw stops turning, the damn thing will sink until the control team get the tanks set for neutral or positive buoyancy. Not a comfortable time as the boat heads down and the hull groans and creaks and everyone starts to wonder if there's enough high pressure air in reserve to blow the tanks.
Mainly OT, but by God and by golly, major navies do FLY their subs.
Parent
Re: (Score:3)
On to my point...
Fine -- so a slight negative buoyancy is augmented by some flying with the dive planes. Nevertheless, a submarine, unlike an airplane is *not* dependent upon forward motion to rise to the surface. A submarine, unlike an airplane, primarily uses ballast and or air to at least approximate the buoyancy of an equal volume of water. Whether or not it *augments* this equilibrium with fo
Re: (Score:3, Insightful)
The deepest diving subs do not use air to surface but lighter than water hydrocarbons, as at higher pressure the air compresses more, displaces far less water, so they can only make one trip to the bottom, then drop ballast and rise to the surface. An incompressible positively buoyant craft can make many trips to the bottom, the catch is the deeper it want to go, the more force is required ie. the faster in must fly through the water, oddly similar to planes.
Of course to correct your other error, you cou
Skydiver (Score:2)
First thing that came to mind for me is from the old UFO series http://en.wikipedia.org/wiki/SkyDiver [wikipedia.org]
The idea of JATO (or is that RATO) assisted launches from underwater would make for some interesting dynamics, yet I think that space borne items will be of far more value in the long term, its not like you can't drop from about anywhere up there and end up where you want to be while a submersible is subject to being easily interdicted
Crazy DARPA (Score:5, Funny)
Re:Crazy DARPA (Score:5, Funny)
You're on the right track. Imagine a submersible aircraft carrier that launches flying submarines. Consider your mind blown.
Parent
Re:Crazy DARPA (Score:5, Insightful)
Can I buy some pot from you?
Parent
Re: (Score:3, Funny)
The summary forgot to mention the requirement that the vehicle must also have a screen door.
maybe it would be easier (Score:5, Funny)
Already been done (Score:2)
Re: (Score:3, Interesting)
Would the nuclear B-36 [archive.org] count? It wasn't nuclear-powered but it did have an operational power-producing nuke running in it when it was flying, with the intent to develop it into a fully nuclear-powered aircraft using a General Electric HTRE nuclear aircraft engine. It was as heavy as many subs and you had to crawl around through it, using a rope-pulled trolley to get from the front to the back.
Re: (Score:3, Interesting)
For extra credit, create a vehicle that can fly, go into space and submerge to the deepest portions of the ocean.
Steve Fosset (Score:5, Funny)
I don't have anything to say, but everybody else is posting stuff with "Steve Fosset" as the title.
Steve Fosset (Score:5, Funny)
I don't have anything to say either.
Parent
Steve Fosset (Score:3, Funny)
Well, i have lots to say!
I just don't feel like saying it.
-Taylor
Roger Penrose (Score:5, Funny)
What? Oh sorry, wrong door.
Parent
TPM (Score:4, Funny)
Re: (Score:3, Informative)
Does Phantom Menace even have a flying submarine? It has a regular submarine...
But anyway, obviously the correct reference is to the submersible squadron from Sky Captain and the World of Tomorrow. Der. Plus: Angelina Jolie!
This is Voyage to the Bottom of the Sea (Score:4, Informative)
Let's See. (Score:5, Funny)
Rocks sink, and Rocks Fly. Problem Solved!
Re: (Score:3, Insightful)
I'm not sure (Score:4, Funny)
I'm not sure, but I believe those "underwater airplanes" already exist.. and are called "submarines".
start with mother nature (Score:5, Interesting)
study up on flying fish [wikipedia.org] and flying squid [wikipedia.org]
then dabble in cormorants [wikipedia.org] and water beetles [everythingabout.net]
once again, mother nature was here first and has a lot to teach us about where to start
i've seen them fly in the philippines (Score:3, Interesting)
http://www.susanscott.net/Oceanwatch2002/jan04-02.html [susanscott.net]
Water is 830 times more dense than air (Score:5, Insightful)
Re: (Score:3, Interesting)
Re:Water is 830 times more dense than air (Score:5, Funny)
My disgust for it grows geometrically every time I read it.
Parent
The scifi version would be supercavitating subs (Score:5, Informative)
Supercavitation [wikipedia.org] would allow submarines to move at supersonic (with reference to water) speeds while submerged, and dogfight underwater [space.com] like WWI aircraft did in the air. If they can come to a complete stop they'd be silent and invisible, just floating there, then fire up the engines and go back to moving faster than ship-based sonar would be able to detect them. There's already a supercavitating torpedo [wikipedia.org]. People who design targets -- I mean aircraft carriers and destroyers -- must be worrying about this.
Re: (Score:3, Informative)
Although, I think a supercavitating submarine is way cooler, they are basically looking for a seaplane [wikipedia.org] that c
Re: (Score:3, Interesting)
Supercavitation would allow submarines to move at supersonic (with reference to water) speeds while submerged
Wait, you mean faster than the speed of sound under water? If that's what you meant, no way, we can't make things move that fast in air, so how can an object basically traveling in an underwater air bubble move that fast? The fastest torpedo listed on the wiki page is a 2004 German torpedo which it says reaches 800km/h, which is 3/4ths the speed of sound in air, which is itself around 1/5th the spe
Re:The scifi version would be supercavitating subs (Score:4, Insightful)
Parent
Re:The scifi version would be supercavitating subs (Score:4, Interesting)
Supercavitation would allow submarines to move at supersonic (with reference to water) speeds while submerged, and dogfight underwater like WWI aircraft did in the air.
The last I heard any vehicle making use of supercavitation is not able to turn (or at least not very quickly) at supercavitating speeds while underwater. It would be like a car turning suddenly in a long, narrow, and straight tunnel through solid rock (with similar results). The Skvahl [wikipedia.org] torpedo, for example, is said to have this limitation (i.e. it is a straight shot weapon with no ability to correct course once it has been fired and is up to speed).
Parent
My inexpert take. (Score:3, Interesting)
The concept may date back a long time (Score:3, Interesting)
I then put two and two together and got five, because I realised that the disagreement arose because the interviewer did not expect the operating temperature range of the hardware to exceed more than about 25 degrees C - which made sense if it was for use in sea water.
Requisite Futurama Quote (Score:5, Insightful)
"How many atmospheres can this ship take?"
"Well, it's a spaceship, so I'd say anywhere between 0 and 1."
Faster than the speed of sound (Score:3, Funny)
I'm waiting for the sonic boom.
What is up with the tags recently? (Score:5, Insightful)
Re:What is up with the tags recently? (Score:4, Insightful)
since when is "fuckofftags" a useful tag?
Not useful. Popular.
Parent
diametrically opposed is good! (Score:5, Insightful)
They're saying how the requirements for submersibles and aircraft are diametrically opposed. That's good! If they were only kinda in opposite directions, that'd be a challenge. But calling on my vast electrical engineering knowledge (and what is mechanical engineering but electrical engineering with molecules instead of electrons?), I can tell you this is easy. What do you do if you discover that your current is diametrically opposed to what you want? That's right, you flip the terminals around, and bam your current is spot on!
So, using the same principle. In air you want the plane light and lift high because gravity means the natural tendency of the plane is to go downward and you want to go up. Underwater, gravity turns into buoyancy and your plane would naturally want to go up when you want it to go down. This sounds like our current problem -- we have a plane that flies perfectly in air, but in water goes the opposite direction of what we want. So what do we do? Yeah, we just flip it. Now the "lift" of the wings is pointed down. All you need then is an engine that works in air and water, and either a crew compartment that rotates to stay vertical, or sturdy straps and training for pilots to maneuver while upside-down. Done!
I just but the reversed-wing thing is actually used in some high speed submersible. Exercise on how to make it work in either direction above/below water left as an exercise for the DARPA grantee.
When I was in the Navy.... (Score:3, Funny)
These two guys didn't get along.
In one (of many) knock down drag 'em out verbal exchanges the two had, the Captain yelled at the XO,
"There are more helicopters at the bottom of the sea then there are submarines in the sky!!"
Yeah, that will fly.... (Score:3, Funny)
Slashdotters need to get out more (Score:3, Informative)
This type of object exists, we HAVE flying submaringes, they are called BIRDS. Diving birds are NOT constrained by their weight. Their problem is their lungs. Several spieces swim very well under water and can even go straight from flying to submerged.
If birds can do it, so can man.
The trick is to stop thinking of this object as an old fashioned submarine and accept that modern submarines FLY under water. They use their "wings" to control their movement, not their weight.
The biggest challence is re-configuring the wings. Birds can do this easily but swing-wing is out of fashion for a reason. A swing wing that can survive a dive is going to be a major piece of engineering.
Another challenge is getting from one method of propulsion to the other. Birds of course use the same engine and switch effortleslly between legs and wings for power, can humans do the same? Have a single engine that can power motion in air and underwater?
There is however one part of the requirement that might make it more difficult. I think this aircraft is intended for the insertion of seal units quickly without having to worry about air defences. For the seals to disbark from the aircraft underwater it would have to be going very slow or even be motionless. An aircraft that is light and uses negative lift to remain submerged would shoot up like a cork if it stopped.
Key problems:
Power source that can operate underwater.
Two modes of propulsion for air and water.
Switching quickly between modes and both modes not interfering with the other, for instance propellors would probabbly smash during a power dive.
Being able to remain motionless underwater and also submerged.
If it wasn't for the last requirement the trick would be fairly simple, "just" a plane that has positive lift in the air, negative lift under water, super-cavitation speeds to be able to shoot up out of the water with enough speed to remain airborne and a system to switch seamlessly between air and water propulsion.
Do-able. But remaining motionless underwater adds a whole new trick. Suddenly you can use your speed and re-use your wings to remain underwater, you need to alter your weight.
Mind you, I wonder if we at slashdot are not overcomplicating things. What DARPA is looking for is a way to insert seals with minimal detection.
What about an 'ordinary' sea plane that instead of sitting above its floaters can sink beneath them? Imagine an ordinary plane with floaters attacked sticking out the sides and below. It lands on the water as all seaplanes do but then the floaters rotate above the fuselage allowing to disappear beneath the waves. The fuselage opens, allowing sea-water inside removing most of its lift. The floaters act like miniature subs and can submerge to an extent. This aircraft is not about setting records, it has to operate near the coast anyway so can't go to deep in any case.
Re: (Score:3, Insightful)
Re:Steve Fossett (Score:5, Funny)
This was Fossett's project I believe. They already have a design and partial prototype yes?
I think they've built a prototype, yes. Unfortunately, the test of the prototype of Fossett's follow-on project, an airplane that can fly underground, ended in disaster.
Too soon?
Parent
Re: (Score:3, Funny)
Re:WTF? Why am I paying for this? (Score:5, Funny)
You gotta keep scientists off the streets and out of trouble somehow.
Parent